Roller compactors are often used for densification and dry granulation of powdered material. The roller compactor compacts the powdered or granular material between two rollers under pressure to produce uniform sheets of compacted powder, with a desired hardness and density. The compacted sheets can then be used to manufacture granules for various purposes, such as free flowing granules for automatic packaging of products, high density granules for reduced product packaged sizes, and granules for high speed tableting or encapsulation, with consistent dust-free purity and size.
In a conventional roller compactor machine, powder material from a hopper is pre-compacted with a screw feeder that delivers the powder to the rollers. The screw feeder may be tapered straight, helical, or a combination tapered and straight screw, as described in U.S. Pat. No. 7,384,256.
Some types of material do not compress consistently. For example, some types of powdered active pharmaceutical ingredients (API) passed through a roller compactor product granule with varying compression results, resulting in tablets with variable characteristics due to particulate size variation, crystal morphology, reaction to heat or pressure, and/or chemical variability from differing suppliers.
Therefore, a primary objective of the present invention is the provision of an improved roller compactor which mitigates compression variability of powdered materials.
Another objective of the present invention is the provision of a roller compactor using steam treatment to enhance powdered material compression.
A further objective of the present invention is a provision of a roller compactor having steam added adjacent the nip zone to improve compaction of powdered material by the rollers.
Still another objective of the present invention is a provision of a method of producing a compressed product from powdered material using a roller compactor machine with steam.
A further objective of the present invention is the provision of an improved roller compaction machine for compacting powdered materials into sheets having consistent compression characteristics.
Another objective of the present inventions is the provision of an improved roller compaction machine which compacts powdered material which does not compact well in conventional roller compactor systems.
Yet another objective of the present invention is the provision of a compacted API product made by introducing moisture adjacent the nip zone of a roller compactor so as to minimize compression variability of the compacted product.
Yet another objective of the present invention is the provision of a compacted API product made by introducing chemicals or reactants adjacent the nip zone of a roller compactor so as to minimize compression variability of the compacted product or to complete a reaction in the raw materials.
Yet another objective of the present invention is the provision is that the where steam or other reactants are introduced the compressed sheet produced does not increase significantly in moisture content.
These and other objectives have become apparent from the following description of the invention.